The 2010 World Cup ball — here comes the science

I’m getting pretty excited about this year’s World Cup. It’s a fun tournament and a truly international sporting event. There’s already been some controversy over this year’s ball, so how did it perform in the lab? Here’s research from the University of Adelaide.

“The Jabulani is textured with small ridges and ‘aero grooves’ and represents a radical departure from the ultra-smooth Teamgeist ball, which was used in the last World Cup,” says Professor Derek Leinweber, Head of the School of Chemistry & Physics at the University of Adelaide, who has previously written about and lectured on the aerodynamics of cricket balls, golf balls and the 2006 World Cup soccer ball, the Teamgeist.

Along with student Adrian Kiratidis, who is studying for his Master of Philosophy (MPhil) in Physics, Professor Leinweber has been reviewing the physics behind soccer balls and what that means for the Jabulani. Adrian is also a soccer enthusiast.

“While the governing body FIFA has strict regulations on the size and weight of the balls, they have no regulations about the outside surface of the balls,” Professor Leinweber says.

“The Teamgeist was a big departure at the last World Cup. Because it was very smooth – much smoother than a regular soccer ball – it had a tendency to bend more than the conventional ball and drop more suddenly at the end of its trajectory.

“By comparison, the aerodynamic ridges on the Jabulani are likely to create enough turbulence around the ball to sustain its flight longer, and be a faster, harder ball in play.

“The Jabulani is expected to ‘bend’ more for the players than any ball previously encountered. Players are also discovering new opportunities to move the ball in erratic ways, alarming the world’s best goalkeepers. By the time the ball reaches the goalkeeper, the Jabulani will have swerved and dipped, arriving with more power and energy than the Teamgeist.”

University of Adelaide students have also put the new World Cup soccer ball to the test on the soccer field. Based on Professor Leinweber’s theories, they’ve attempted to “bend” the Jabulani and have also kicked the Teamgeist and a regular soccer ball for comparison.